GB2469571A

GB2469571A - Capacitor mounting in a switch subassembly

Info

Publication number: GB2469571A
Application number: GB1006232A
Authority: GB
Inventors: Csaba Kreiter; Jan Koegel
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2009-04-15
Filing date: 2010-04-14
Publication date: 2010-10-20
Anticipated expiration: 2030-04-14
Also published as: US8357869B2; CN101866763A; GB201006232D0; DE102009002382A1; GB2469571B; US20100264009A1

Abstract

A switch component 10 for a switch subassembly 100 comprises a switch housing 12 with an electrical contact region 30 and a receiving region 20 for a capacitor element 60, and control elements 50, 54, 56. The capacitor element 60 is insertable by contact elements 70, 72 thereof into the receiving region 20 of the switch housing 12, the receiving region preferably being of pocket-like form and having a detent projection 22 co-operable with a detent recess 80 of the capacitor element so as to securely fasten the capacitor element to the switch housing. The securely fastened, but detachable, capacitor element can be provided in different forms for use with one form of switch component. Cables can be connected to contact bushes 32-38 using a slide mechanism 36 and pass through cable comb 24 on the housing and cable comb (fig 2, 86) on the capacitor. The capacitor can comprise further contact elements 74,76 that project outwardly when the capacitor is inserted, to connect an electrical component, and a discharge resistor (fig 6, 78). The switch subassembly can be used in the handle of an electrical power tool such as a keyhole saw (fig 7, 200).

Description

CAPACITOR MOUNTING IN A SWITCH SUBASSEMBLY

The present invention relates to a switch component for a switch subassembly with a capacitor and to a capacitor for a switch subassembly.

The most diverse forms of switch subassemblies are used in electric tools. Such switch subassemblies can be equipped with, for example, anti-interference capacitors. Switch subassemblies in which discharge resistances are integrated in the anti-interference capacitor are also known. A multiplicity of different switch subassemblies is needed for different apparatus requirements.

According to a first aspect of the invention there is provided a switch component for a switch subassembly, comprising a switch housing, an electrical contact region, a control element and a receiving region for a capacitor element, wherein the capacitor element is insertable by its contact elements into a receiving region of the switch housing.

Advantageously, the capacitor element is separable from the switch component, wherein the capacitor element is preferably connectible with the switch component by a plug connection. The plug connection can be produced by means of, for example, mechanical connecting elements such as snap hooks, clamping connections or the like. The capacitor can be connected with the switch housing with high positional accuracy. Security against swinging out of the capacitor element can be improved.

One design of the switch housing can be used for an apparatus series or even an entire apparatus platform, in which case, for example, only the capacitor element has to be adapted to the requirements specific to the apparatus line or specific to country, for example radio interference suppression requirements.

According to an advantageous embodiment the receiving region for reception of the capacitor element can be of pocket-like form. The capacitor element can be inserted and retained with high positional accuracy, so that even in operation, particularly in the case of vibrations, the electrical and mechanical connection between capacitor element and switch housing can be guaranteed.

According to an advantageous embodiment the capacitor element can have two contacts which in the inserted state of the capacitor element project outwardly of the switch housing for connection of one or more electrical components. Advantageously, such output points of the capacitor element can be used for voltage supply of components. Thus, the input potential at the contact elements of the capacitor element can experience a potential change in the capacitor element so that a different output potential is available at the outputs. Consequently, by means of the difference primarily of the capacitor element output potential it is possible for components such as, for example, lighting means and/or a laser diode or other apparatus-specific power features to be supplied with the required electrical potential in, for example, a keyhole saw or other type of electric power tool.

According to an advantageous embodiment the switch housing can comprise one or more detent elements for locking the capacitor component. The capacitor element can thereby be securely and stably held in the switch housing.

According to an advantageous embodiment the switch housing can have a cable comb which when the capacitor element is inserted can rest on an outer side of a housing of the capacitor element and can have one or more receptacles for parallel guidance of one or more cables. In particular, the cable comb can co-operate with a cable comb at the capacitor element. Advantageously, cables can be held in directionally oriented manner.

The cables can be clamped in simple manner by the cable comb, which facilitates assembly. Through provision of one or more cable combs on the capacitor element it is possible to take individual electromechanical requirements into consideration in simple manner in that different receiving openings in the cable comb can be provided for, for example, different cable diameters.

According to an advantageous embodiment the receiving region can be arranged at an end face at the electrical contact region of the switch component. Thus, cables can be conveniently led past the capacitor element and connected with the electrical contact region.

According to an advantageous embodiment the electrical contact region can have electrical contact bushes for cables. In particular, cables can be clamped in or released from the plug contacts by a slide mechanism. Such a slide mechanism can be a quick-release mechanism in which the contact bushes are freed by movement of the slide mechanism in one direction so that cables can be plugged in and in which, on movement of the slide mechanism in the opposite direction, the cables can be clamped in the contact bushes.

According to a second aspect of the invention there is provided a switch subassembly comprising a switch component, a switch housing, an electrical contact region, a control element and a receiving region for a capacitor element, wherein the capacitor element is inserted by its contact elements into a receiving region of the switch component.

Advantageously, the switch subassembly can be used for different apparatus. In particular, depending on the respective apparatus requirements different capacitors can be used with switch components of the same kind, for example in the case of different radio interference suppression requirements, regionally different requirements, different apparatus types and the like. Advantageously, corresponding modular dimensions can be standardised. In the case of development of an apparatus line or an entire apparatus platform it is possible, for example, for constructionally defined regions to be provided in the switch subassembly or in the switch housing for a capacitor element which has the same dimensions and plug contact arrangements for connection with the switch housing.

Thus, switch subassemblies can be produced more economically by virtue of a significantly increased number of identical parts.

According to a third aspect of the invention there is provided a capacitor element for a switch subassembly according to the second aspect, wherein the capacitor element has at a housing thereof detent elements which correspond with detent elements in the switch housing of the switch subassembly.

Advantageously, the capacitor element can, according to apparatus-specific or country-specific requirements, be designed with or without a discharge resistance or with or without additional output lines for providing a current supply of components which can be connected with the capacitor element and plugged into a switch housing, which is conceived to be standardised for, for example, an apparatus series or an apparatus platform.

According to an advantageous embodiment contact elements for connection with the electrical contact region of the switch component can be provided on a first end face. In addition, contact elements for connection of one or more electrical components can be provided on an opposite, second end face. The capacitor element can be used in order to provide an additional voltage potential for power supply of components.

According to an advantageous embodiment an electrical resistance arranged within the capacitor housing can be provided. The electrical resistance can, as a discharge resistance, improve the function of the capacitor element.

According to an advantageous embodiment a cable comb can be arranged at the capacitor housing. Advantageously, cables can be held in directionally oriented manner by means of, for example, clamping in the cable comb. Mounting of the cables can be simplified and the cables can be accommodated in space-saving manner.

Embodiments of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Fig. la is a schematic perspective view of a switch subassembly embodying the second aspect of the invention and inclusive of a switch component embodying the first aspect of the invention, showing a plugged-in capacitor element embodying the third aspect of the invention; Fig. lb is a view corresponding with Fig. la, but showing the capacitor element unplugged; Fig. 2 is a view similar to Fig. Ia, but showing a different embodiment of capacitor element together with connected cables; Fig. 3 is a schematic diagram of part of a quick-release plug connection of the cables in Fig. 2; Fig. 4a is a perspective view, from one side of a capacitor element embodying the invention; Fig. 4b is a perspective view of capacitor of Fig. 4a from an opposite side; Fig. 5 is a perspective view of a further capacitor element embodying the invention; Fig. 6 is a cross-section of a capacitor element embodying the invention, showing an integrated discharge resistance; and Fig. 7 is a side view of an electric power tool incorporating a switch subassembly embodying to the invention.

Referring now to the drawings, in which corresponding components of different embodiments of the invention are denoted by the same reference numerals, Figs. la and lb show a switch subassembly 100 embodying the invention and comprising a switch component 10, an electrical contact region 30, three control elements 50, 54 and 56, and a receiving region 20 for a capacitor element 60. The capacitor element 60 can be plugged by contact elements 70 and 72 thereof (Fig. ib), which are preferably constructed as contact pins, into the receiving region 20 of a switch housing 12 of the switch component.

Fig. la shows the capacitor element 60 in the plugged-in state and Fig. lb shows the capacitor element 60 in the unplugged state and separate from the switch component 10.

The control element 54, for example a slide switch or a press switch is, in the installed state of the switch subassembly 100 in an apparatus, such as an electric power tool, externally actuable by a user. The control element 54 serves as a main switch, i.e. on-switch of the power tool. The control element 54 with a frame 52 is arranged on a rearwardly extending electrical contact element 26.

Arranged below the control element 54 or the electrical contact region 30 is the control element 50, by which, when the main switch is switched on, operation of the power tool is set in motion. The control element 50 is, for example, constructed as a latch switch and can be constructed to be single-stage with a 0/1 signal setting or to be stepless. If the control element is actuated, for example, pressed upwardly, the power of the tool increases, for example stroke rate or speed of a saw blade in the case of a keyhole saw, with the advantage of direct control of the saw speed during the sawing process.

Arranged at the underside of the control element 50 is a setting element 58 which is, for example, constructed as a rotary button and which enables speed preselection.

The electrical contact element 26 extends rearwardly to the rear control element 56. The control element 56 serves, in a first embodiment, for locking the control element 50 in a pressed-in state and is preferably constructed as a purely mechanical lock, which is spring-mounted in both directions of actuation. The switch element 50 is pressed as far as a stop and the control element 56 moved either into or out of the apparatus. If the control element 56 is still pressed in, the control element 50 can be released and will remain in a detented setting. The user can work conveniently, since it is not necessary to constantly actuate the control element 50.

The control element 56 can in a further embodiment, for example in the case of a hand circular saw, be used as a switch-on block as a safeguard against unintended switching-on of the saw. The control element 50 can, for example, be actuated only when the control element 56 is displaced to an end stop.

The receiving region 20 for reception of the capacitor element 60 is constructed in the switch housing 12 and of pocket-like form. The switch housing 12 has a partly open rear side 14, an upper lateral guide 16, a lower lateral guide 18 and a front side 24a, which is constructed as a cable comb 24. The capacitor element 60 can be pushed into the pocket-like receiving region 20 with positional accuracy and retained. The capacitor element 60 nests by a housing 62 thereof closely against the rear side 14, the lateral guides 16, 18 and the front side 24a of the receiving region 20, so that the capacitor element can be held with positional accuracy even in constant use.

The switch housing 12 has at the receiving region 20 one or more detent elements which lock the capacitor element 60, in the plugged-in state, in the receiving region 20. Thus, for example, a detent element 22 in the form of a snap hook is provided, which, when the capacitor element 60 is plugged in, snaps over the free end face 66 of its housing 62.

In the illustrated embodiment the capacitor element 60 has two contacts 74 and 76, which in the plugged-in state of the capacitor element protrude outwardly of the switch housing 12. The optionally provided contacts 74 and 76 serve for connection of one or more electrical components which, for example, need a voltage potential separate from the capacitor element 60 or switch subassembly 100 itself.

The capacitor element 60 has at the housing 62 a detent recess 80 which corresponds with the detent element 22 of the switch housing 12. In addition, provided at the lateral flanks of the capacitor element 60 are detent nubs 82 and 84 which correspond with detent elements (not recognisable in the drawing) in the switch housing 12 of the switch subassembly 100.

The receiving region 20 abuts at the end face against the electrical contact region 30 of the switch housing 12, in which counter-contacts, for example plug bushes, for the contacts 70, 72 of the capacitor component 60 are arranged. The contacts 70 and 72 are arranged at the end face 64 of the capacitor element 60 opposite the end face 66 and can be seen in Fig. ib, where the capacitor element is shown unplugged.

The electrical contact region 30 has electrical contact bushes 32, 34, 38 and 40 for cables, which when plugged into the contact bushes 32 and 34 can be clamped or released by a slide mechanism 36. The cables can be inserted transversely to the length direction of the switch component 10 or switch subassembly 100.

Fig. 2 shows, as a detail, a switch subassembly 100 corresponding with the embodiment described in Figs. la and ib, wherein in the electrical contact region 30 cables 90, 92, 94 and 96 are inserted into the electrical contact bushes 32, 34, 38 and 40.

A further cable 98 is clamped at the upper side surface 16 of the switch housing in a corresponding mount.

By contrast to the embodiment in Figs. 1 a and 1 b, to which reference is made for detailed description of the components, not only the switch housing 12 has a cable comb 24, but also the capacitor element 60, on the housing of which a corresponding cable comb 86 is arranged. Connecting cables can in this manner be quickly and securely fixed to the switch subassembly 100.

Two cables 90 and 94, which are, for example, connectible with a load L, can be clamped in or released from the contact bushes 32 and 34 by the slide mechanism 36 (quick-release mechanism) and can be pushed in a single working step into the contact bushes 32 and 34. This is illustrated in more detail in Fig. 3. The inserted cables 90 and 94 can, after insertion, be clamped in the contact bushes 32 and 34 by manipulation, parallel and without a tool, of the slide mechanism 36. The movement path for opening and closing the slide mechanism 36 is indicated by a double arrow.

Figs. 4a and 4b show an embodiment of the capacitor element 60 in different views.

The contact elements 70 and 72 for connection with an electrical contact region 30 of the switch subassembly 100 (Figs. la, lb and 2) are provided on the first end face 64. The capacitor element 60 is plugged into the electric contact region 30 by these contacts, which are constructed as contact pins.

The contact elements 74, 76 for connection of one or more electrical components are provided on the opposite, second end face 66. Provided at the side surfaces of the capacitor housing 62 are the contact nubs 82 and 84 serving for detenting in corresponding detent elements of the switch housing 12. The detent recess 80 in the capacitor housing 62, which recess is arranged to correspond with the detent element -for example constructed as a snap hook -of the switch housing 12, can be seen in Fig. 4b.

The capacitor housing 62 does not have a cable comb in this embodiment. A variant of a capacitor element 60 is illustrated in Fig. 5, in which the cable comb 86 is arranged at the capacitor housing 62. The embodiment otherwise corresponds with that of Figs. 4a and 4b.

Fig. 6 shows a longitudinal section through a capacitor element 60 in correspondence with the embodiments in Figs. 4a, 4b and 5. An electrical resistor 78, which is arranged within the capacitor housing 62, is electrically connected in series with the contact elements 70 and 72 at the side of the switch component. The resistor 78 is provided as a discharge resistance which protects the capacitor element 60 or electrical components connected therewith in the case of an electrical short-circuit. The resistor 78 is cast together with the actual capacitor 60a in the capacitor housing 62.

Fig. 7 shows, by way of example, an electric power tool 200 which is constructed as a keyhole saw and in which the switch subassembly 100 (Figs. Ia, Ib, 2) is incorporated in a handle 210. The control element 50 and the control element 56 can be seen, which are arranged ergonomically and permit convenient control of the electric power tool 200.

Claims

CLAIMS1. A switch component for a switch subassembly, comprising a switch housing with an electrical contact region and with a receiving region for a capacitor element insertable by contact elements thereof into the receiving region, and at least one control element.
2. A switch component according to claim 1, wherein the receiving region defines a pocket-like receptacle for the capacitor element.
3. A switch component according to claim 1 or claim 2, wherein the switch housing comprises at least one detent element for locking the capacitor component to the housing.
4. A switch component according to any one of the preceding claims, wherein the switch housing comprises a cable comb, which when the capacitor element is inserted rests on an outer side of a housing of the capacitor element and which has a receptacle for guidance of a cable or a plurality of receptacles for parallel guidance of a plurality of cables.
5. A switch component according to claim 4, wherein the cable comb is co-operable with a cable comb at the capacitor element.
6. A switch component according to any one of the preceding claims, wherein the receiving region is arranged at a side of the electrical contact region.
7. A switch component according to any one of the preceding claims, wherein the electrical contact region is provided with electrical contact bushes for cables.
8. A switch component according to claim 7, wherein the electrical contact region is provided with a slide mechanism for clamping the cables in or releasing the cables from the contact bushes.
9. A switch subassembly comprising a switch component according to any one of the preceding claims and a capacitor element inserted by contact elements thereof into the receiving region of the switch housing.
10. A subassembly according to claim 10, wherein the capacitor element comprises at least one further contact element which in the inserted state of the capacitor element projects outwardly of the switch housing and serves for connection of an electrical component.
11. A capacitor element for a switch subassembly according to claim 9 or claim 10, wherein the capacitor element comprises a housing with detent elements corresponding with detent elements at the switch housing of the switch component of the subassembly.
12. A capacitor element according to claim 11, wherein the housing of the capacitor element is provided on an end face thereof with contact elements for connection with the electrical contact region of the housing of the switch component of the subassembly.
13. A capacitor element according to claim 12, wherein the housing of the capacitor element is provided on an end face thereof opposite the first-mentioned end face with further contact elements for connection of one or more electric components.
14. A capacitor element according to any one of claims 11 to 13, comprising an electrical resistor arranged within the capacitor housing.
15. A capacitor element according to any one of claims 11 to 14, comprising a cable comb arranged at the capacitor housing.